Vacuum excavation, which is also referred to as hydro excavation, is a process of excavating a soil with a jet of pressurized water and an air vacuum system. Pressurized water is injected to break up and cut soil while the air vacuum system operates to remove debris to a debris collection tank.
In certain applications, the pressure of discharging water should be limited to a certain level to ensure operators' safety and prevent destruction of underlying infrastructure. Accordingly, vacuum excavation processes typically need to meet guidelines for maximum operating water pressures in different situations. Such guidelines are provided by several organizations, such as Gas Technology Institute (GTI), Occupational Safety and Health Administration (OSHA), and Technical Standards and Safety Authority (TSSA) in Ontario, Canada. Operators of vacuum excavation equipment are required to operate the equipment at a proper water pressure for a given circumstance. Operators are typically responsible for selecting a nozzle connected to a water pump and manipulating a water pump controller to properly set the water pump to a safe water pressure.